Levitra, Like Viagra, Is a PDE-5 Inhibitor Which Relaxes the Smooth Walls of Blood Vessels

How Levitra Works

Levitra belongs to a class of drugs called PDE-5 inhibitors. That means that, just like Viagra and Cialis, the medication is an inhibitor of type 5 phosphodiesterase (PDE). For those in the audience without a medical background or a degree in biology, what that means is that Levitra relaxes the muscles at the base of the penis allowing more blood to flow into it and thereby produce an erection.

Levitra is taken orally and is available in 2.5 milligram (mg), 5 mg, 10 mg, and 20 mg tablets. The drug is to be taken as needed but not more than once a day. As a result of taking Levitra, or any of the other PDE-5 inhibitors, men with erectile dysfunction (ED) are able to achieve and maintain an erection long enough for successful sexual activity. After sex, blood flow should decrease and the erection should go away.

Big Science

Research into this class of drug has been big news ever since the 1998 release of a drug called sildenafil, better known by its brand name – Viagra. While Viagra vastly affected the drug industry, bringing record profits to its manufacturer, pharmaceutical giant Pfizer Inc., it also grew out of a major scientific discovery. The discovery was so major it earned its three American discoverers the 1998 Nobel Prize in physiology. What the three pharmacologists, Robert F. Furchgott, in New York, Dr. Ferid Murad, in Houston, and Louis J Ignarro, in Los Angeles, discovered involves PDE, the breakdown of cyclic guanosine monophosphate (GMP), intracellular mediators, and the “nitric oxide (nonadrenergic, noncholinergic) pathway,” according to the Urological Sciences Research Foundation (UARF).

What all those really big words mean is that the scientists found a way to relax the smooth walls of blood vessels, allowing more blood to flow, by inhibiting PDE. PDE interactions restrict blood flow. Type 5 PDEs are concentrated in the penal region and — when properly inhibited — sexual stimulation produces an erection for men with ED.

Big Money


It does not take a Nobel Prize winner to know that being able to produce erections on demand for men suffering from ED also would lead to big business. More than 20 million men have been treated with Viagra and more than 1,100 peer-reviewed articles have been written about the drug. If Viagra is so good, why did the market need other medications? In the case of Levitra, the marketing is about “erectile quality,” or “EQ” as the drug’s website calls it. Essentially, Levitra is claiming it does a better job than Viagra. Conversely, the third major ED medication, Cialis, bases its appeal on that it works for up to 36 hours, while both Levitra and Viagra are effective for shorter periods of time.

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